Xcode 7 how do you refresh provisioning profiles?

You can delete directly your Provisioning Profiles by running:

rm /Users/[userName]/Library/MobileDevice/Provisioning\ Profiles/*

Then re-download your profiles, Xcode -> Preferences -> Account -> View details... -> Download All

Your list in Target -> Build settings -> Code signing -> Provisioning Profiles will be updated.

YM

Xcode 7 should automatically refresh your profiles locally when a change occurs to a profile in the Developer Portal. However, you can force this to occur by deleting and re-downloading the profiles.

Begin by opening Xcode's preferences window (Command+,). Select the Accounts tab, and click the "View Details…" button. In the bottom list that appears, Shift+click or click+drag to select the profiles you'd like to refresh. Then, right-click one of the selected profiles, and choose "Move to Trash" from the contextual menu.

Once that's done, the "Download All" button should pull down fresh copies of everything in the Apple Developer portal.

Profiles not deleting? Per feedback in the in the comments below, if you delete a very large number of profiles, Xcode may appear to do nothing, despite having actually removed all of the selected profiles. If you believe that this is the case, it may help to restart Xcode.

Be sure to take care when selecting profiles to delete… if they're not in the portal (e.g., they were supplied by another developer), Xcode can't automatically get them back for you. If you accidentally delete such a profile, you can find it in the Trash.